Urethral stricture is a very frequently encountered disease. In this disease there is a narrowing of the urethral tube, the tube that delivers urine from the urinary bladder out of the body. This narrowing results from injury or destruction of lining of the urethra. Healing at the injury site produces a scar that contracts to narrow the urethral lumen. Urethral strictures can occur anywhere along the urethra, and they reduce the diameter of the urethra hence this disease is characterized by difficulty in passing urine, thin urinary stream and straining while passing urine. Urethral strictures are more common in men than in women and children.
Some possible causes of injury or destruction of urethral lining leading to stricture are trauma to the pelvic area, sexually transmitted diseases and urethral instrumentation.
- Accidents: The urethra can get damaged when injury occurs in the area beneath the scrotum, or the hipbone is fractured in an accident.
- Infection: Gonorrhea is notoriously known to cause bad strictures. This infection is a sexually transmitted disease given most commonly by professional sex workers.
- Any intervention via urinary passage: Urinary tubes (catheter) put in for any reason or intervention for urologic endoscopic surgery like one for prostate or stones can lead to stricture.
- Other causes: Rarely stricture can be congenital or no obvious cause may be found.
What are the signs and symptoms of urethral strictures?
Urethral stricture is suspected in a patient with complaints of a decrease in the calibre of urinary stream, straining while passing urine, pain during urination and difficulty in urinating. This may be associated with hematuria (blood in urine), abdominal pain, or urethral discharge. Voiding (emptying bladder) may require more time and there is a sensation of incomplete emptying of the bladder. There may a frequent need to urinate during the day and night.
What investigations are necessary prior to treatment?
A patient needs to undergo basic blood and urine tests apart from an abdominal sonography. A urinalysis and a urine culture are done to rule out urinary infection. Tests may be done for Chlamydia, gonorrhoea and other sexually transmitted diseases. Urinary flow rates are measured. An X-ray (Ascending Urethrography) confirms the diagnosis, wherein contrast medium is injected in the urethral tube to outline the urethra and to define the extent of the stricture. Cystoscopy (telescopic inspection of the urethra and bladder) that is done during treatment will finally confirm the diagnosis.
Complications of urethral stricture disease
Urethral strictures obstruct the flow of urine from the bladder, making it difficult to pass urine. The bladder must work harder to push the urine through the narrowed area. If this stricture is not treated, the increased strain on the bladder can weaken the bladder muscle. The combination of a narrowed urethra and a weakened bladder can lead to several serious problems:
- Urine retention: the inability to pass urine
- Urinary incontinence: the involuntary loss of urine
- Hydronephrosis / Kidney failure: there is swelling on the kidney with reduced function. Bladder muscle damage: the bladder muscle can become permanently weakened
- Reflux: urine flowing back up into the kidney
How are urethral strictures treated?
Once a urethral stricture is diagnosed, it would need treatment on merit. There are many therapeutic options. Among them the commonly used ones are urethral dilatation, visual internal urethrotomy (VIU) and open surgical urethroplasty.
This is the oldest form of treatment for stricture urethra. Here a metal rod, or dilator, is inserted into the penis until it reaches the strictured area of the urethra. The dilator gradually stretches the strictured area open. This process usually involves periodic treatments with progressively larger dilators. Though this procedure is simple, it may have complications like infection, trauma with false passages and bleeding. One of the biggest drawbacks of dilatation is the very high incidence of re-stricture formation. To avoid these complications there have been few modifications.
Clean Self Intermittent Catheterisation (CSIC):
Regular dilatation needs repeated re-treatment hence patient needs repeated visits to the hospital. This amounts to loss of working hours and a lot of expenses. To reduce this selected patients may be put on a schedule of CSIC. Here patient is taught self-dilatation and he does in the privacy of his home using a non-traumatic urethral catheter with all aseptic precautions.
Visual Internal urethrotomy
VIU is a simple treatment for urethral stricture. Today this is the commonest procedure done for this disease.
Here under regional anaesthesia the strictured area is cut open with a cold knife. The procedure is controlled under telescopic vision. After the procedure a catheter is placed in the urinary passage for 24 – 48 hours.
VIU has an advantage over dilatation that this procedure is done under vision hence the incidence of trauma to urethra is very less. The recurrence rate after VIU is less than dilatation though it is still quite frequent. The recurrence depends on the density of the original stricture. VIU cures superficial strictures, but deeper strictures with fibrosis may have a significant recurrence rate. In view of the high recurrence rate patient may have to be put on regular dilations or CSIC to keep the passage open.
Open surgical repair (Urethroplasty)
There are a variety of open surgical procedures, generally called urethroplasty done for stricture urethra. These are done for complicated strictures and post-traumatic strictures. They are also indicated when simple procedures like VIU do not give satisfactory treatment results or have to be repeated too often.
This invasive surgery requires the use of general or regional anesthesia. The diseased urethra is severed in an attempt to remove the strictured area. The two remaining sections of the urethra are then surgically reconnected. In some cases, a graft of skin or oral mucosa may be needed to bridge the defect.
Urethroplasty is a successful procedure in many difficult situations but it involves a major surgical procedure with long hospital stay and long period of catheterization. The major side effects of urethroplasty are infection, stricture recurrence and impotence. Impotence occurs in some patients due to injury to nerves related to erection. These nerves lie in close proximity to the urethra and can be damaged either during the initial trauma or during surgery. Some patients may have a recurrence after urethroplasty hence patients have to be under regular follow-up. Few patients may need CSIC after urethroplasty.
Though urethroplasty is successful in nearly 90% patients it is due to its side effects that alternative but lesser successful procedure like VIU are being tried.
Prevention is better than cure!
Stricture can definitely be prevented. Practicing safer sex behaviours may decrease the risk of contracting sexually transmitted diseases and subsequent urethral stricture.
Early treatment of urethral stricture may prevent complications such as kidney or bladder infection or injury.